Seal for a food container



FIG. 1 is a perspective view of a seal for a food container showing my new design;

FIG. 2 is a front elevation view thereof, the rear and side views being identical thereto;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof. 

The ornamental design for a seal for a food container, as shown and described. 